KOVAR is a registered trademark of Carpenter company in the United States
Kovar alloy is a vacuum smelting of iron, nickel, and cobalt is of low expansion alloy, chemical composition content is controlled within a very narrow range to ensure accurate equilibrium thermal expansion properties. At the same time, manufacturing process strict quality control also ensures the balance of physical and mechanical properties, more suitable for deep drawing, stamping and all kinds of cutting processing.
Seal preparation of kovar alloy
All parts should be made Kovar degassing and annealing in wet hydrogen atmosphere. Hydrogen is injected into the water at room temperature, and the surface of the water is wet and must be carefully prevented from carbonization. The heat treatment furnace should provide the same atmosphere as the cooling chamber. Heat treatment in the 1540/2010 DEG F (838/1099 degrees C temperature range and time of the heat treatment is started from the lowest temperature, 20 minutes to rise to the highest temperature, the parts then moves to the cooling zone, cooling to 570 degrees F (299 DEG C) after the removal.
Metal and hard glass sealing, the metal is best to have a layer of oxide film, the best oxide film is thin and tightly adsorbed on the metal surface.
Magnetic of kovar alloy
Kovar alloys have magnetic in the Curie temperature, the magnetic energy depends on the heat treatment. The hardness of the smaller, higher permeability, smaller hysteresis loss.
Application of kovar alloy:
Vacuum seal for hard glass and ceramic. Widely used in electronic tubes, microwave tubes, transistors and diodes. In the integrated circuit, it is used for flat integrated circuit and dual in-line package.
Kovar (Kovar) ASTM F15 alloy is the most commonly used high integrity control expansion alloy, expansion coefficient and glass ceramics is similar for in ceramic or glass to metal sealing and connecting, mainly used in circuit of the shell, optoelectronic housing, electron tubes, crystal, CRT electron gun parts field.
carbon below 0.02% Mn below 0.30% silicon below 0.20% nickel below 29% cobalt below 17% iron allowance.
Get a quote